Decanting columns



Oct. 22, 1968 N, GREENSMITH 3,406,830

DECANTING COLUMNS Filed May 1l, 1966 2 Sheets-Sheet l Oct. 22, 1968 N.GREENSMITH DECANTING COLUMNS 2 Sheets-Sheet 2 Filed May 1l, 1966 UnitedStates Patent O 3,406,830 DECANTING COLUMNS Norman Greensmith,Horsforth, Leeds, England, assignor to Naylor Bros. (Clayware) Limited,Yorkshire, England, a British company Filed May 11, 1966, Ser. No.549,390 4 Claims. (Cl. ZIO-241) ABSTRACT OF THE DISCLOSURE A decantingcolumn for a sludge draining and drying `bed comprising a base mem-bercarrying a frame, said base member having a liquor outlet therein, anopenended tube slidably and sealingly received into the base member,said tube having a series of restrictions around its inlet, and beingsupported on the frame by a screw threaded rod so as to enable movementof the tube relative to the base member.

This invention relates to a decanting column for supernatant liquids andis particularly concerned with such a column for use with beds fordraining and drying sludge.

According to this inven-tion there is provided a decanting column for asludge draining and drying -bed comprising a base member, a liquoroutlet in said base member, an open-ended tube slidably and sealinglyreceived into the base member, a frame carried by the base member, arestriction device around the free open end of the tube to limit thepassage of solid material into the tube, and means carried by the frameabove the tube for supporting the tube on the trame and for enabling theheight between the liquor outlet and the liquor inlet defined by thefree open end of the tube to be controllably varied by moving the tuberelative to the base member.

Preferably, the restriction device comprises a series of pegs secured tothe tube around the free open end thereof, said pegs extending away fromthe end of the tube and substantially parallel to the axis thereof.

An embodimentI of the present invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is a side view of a decanting column showing in chain-dot linesthe level at which decanting is no longer necessary.

FIG. 2 is a half-sectional side View of the column shown in FIGURE 1.

A sludge liquid decanting column comprises `a base member in the form ofa vitriiied clay sludge bed tile 1 having side outlet openings 1a, witha socket 2 within which a corrosion resistan-t anchor plate 3 issecurely bonded with a filler 4 (FIGURE 2). In the inner surface of anintegral annular plate 5 is mounted on an annular seal 6 which contactsa central decanting tube 7 and enables the tube to slide within the seal6 whilst preventing passage of solid material therepast. Secured to theannular plate 5 are column frame members 8 which support, in a supportcolumn bridge 9, a screw-threaded nut 10 through which a screw-threadedrod 11, carrying an operating handle 12 in the form of `a cross bar,passes. The lower end of the rod 11 is secured to a top bar 13 extendingacross the open top end of the decanting tube 7. Around the top of thetube 7 are located weir pegs 14, between which a supernatant liquor 16may pass into the decanting tube. The materials of the decanting columnwhich come into contact with the liquor 16 to be decanted are corrosionresistant.

CII

3,406,830 Patented Oct. 22, 1968 In operation the decanting column islocated in a sludge draining and drying bed 15 and the top .bar 13 ofthe decanting tube is controlled by rotation of the -bolt 11 to`position the bar 13 just below the surface of the liquor 16 above thesludge so that the liquor 16 drains between the weir pegs 14, into thedecanting column, to pass through the socket 2 to waste whilst thesludge remains.

The weir pegs 14 serve to prevent passage of excessively large solids,though being suticiently far apart to be a negligible obstruction to theHow of liquor and vfor it to be easy to clear away any solids fromabove.

The `amount of liquor 16 in the bed may be decreased by rotating rod 11in a clockwise direction, thus moving the decanting tube 12 verticallydownwards (see FIGURE l). Liquor at a lower level will then be decantedinto the tube 7 `and drained to waste.

The lower level of the tube 7 yand weir pegs 14 as shown in FIGURE 1 isthe level at which no further decanting is necessary, since at thispoint cracking of the sludge occurs.

An extension bar may be attached to the top of rod 11 to raise theoperating handle 12 to the level required.

lt will be appreciated that according to the invention there is provideda simple and convenient decanting column by which the draining level ofthe 'bed may be innitely vari-able and that it is possible that thecolumn may be positioned away from the walls.

What is claimed is:

1. A decanting column for a sludge draining and drying bed, comprising abase member, a liquor outlet in said base member, an open-ended tubeslid'ably and sealingly received into the base member, a frame carriedby the base member, restriction means around the free open end of thetube to limit the passage of solid materials into the tube, and meanscarried by the frame above the tube for supporting the tu-be on theframe and for enabling the height between the liquor outlet and theliquor inlet delined by the free open end of the tube to be controllablyvaried by moving the tube relative to the base member.

2. A decanting column as claimed in claim 1, wherein the restrictionmeans comprises a series of pegs secured to' the tube around the freeopen end thereof, said pegs extending away from the end of the tube andbeing substantially parallel to the axis thereof.

3. A decan-ting column as claimed in claim 1, wherein the means forsupporting the tube and for enabling move- -ment of the tube relative tothe base member includes a screw-threaded rod secured to and rotatablein part of the frame, said rod supporting said tube.

4. A decanting column -as claimed in claim 3, wherein a screw-threadednu-t is provided on the frame, said nut co-operating with the screwthreaded rod.

References Cited UNITED STATES PATENTS 299,821 6/1884 McElroy 210-359 X812,931 2/1906 Kiefer 210--241 X 1,252,573 l/19l8 Holt 210--1661,386,340 8/1921 Wuster 210-359 1,450,545 4/1923 Hans 210-359 X1,960,686 5/1934 Tumim 210-83 2,283,365 5/1942 Heinkel 210--166`2,961,098 11/1960 Nash 210--241 REUBEN FRIEDMAN, Primary Examiner.

I. ADEE, Assistant Examiner.

